Automatic phonograph



Nov. 7, 1950 s. A. STOLBERG 2,529,474

AUTOMATIC PHONOGRAPH Filed Feb. 8, 1947 3' Sheets-Sheet 1 INVENTOR.

Nov. 7, 1950 s. A. STOLBERG AUTOMATIC PHONOGRAPH 3 Sheets-Sheet 2 Filed Feb. 8, 1947 INVENTOR- 61/670 62 5 2 5L681? Nov. 7, 1950 s. A. STOLBERG 2,529,474

AUTOMATIC PHONOGRAPH Filed Feb. 8. 1 47 s Sheets-Sheet s REJ i/ F \OFF 9- IN VEN TOR.

wii im Patented Nov. 7, 1950 AUTOMATIC PHONOGRAPH Sven A. Stolberg, Chicago, 111., assignor, by mesne assignments, to R-aytheon Manufacturing Company, Newton, Mass., a corporation of Delaware Application February 8, 1947, Serial No. 727,363

5 Claims.

The present invention relates to automatic phonographs and more particularl to a stop mechanism for such phonographs for automatically discontinuing the operation thereof following the playing of the last record of a series of records which were initiall disposed in a record stack associated with the phonograph. Specifically, the present invention is an improvement on the invention disclosed and claimed in copending application for Letters Patent of the United States, Serial No. 607,878, filed July 30, 1945, and assigned to the same assignee as the present application.

Automatic p-honographs are in extensive use today particularly combined with radio receiving devices in what is commonly termed as a radio-phonograph combination. A very common form of automatic phonograph includes means for sup-porting a. stack of unplayed records adjacent to and above the turntable from whic stack records are fed one at a time onto the turntable. Such automatic phonographs are adapted to play these records consecutively without requiring any control or assistance from an operator. In the many arrangements used heretofore when the last record has been moved into playing position on the turntable the automatic phonograph will continue to replay that last record until the operator either shuts oiT the phonograph or replaces the records in the record stack which have been moved on to the turntable. In my prior copending application referred to above, there is disclosed an arangement for automaticall stopping the phonograph at the completion of playing the last record from the record stack when it has moved onto the turntable. It would be desirable to provide an improved stop means of sturdy construction, embodying a number of parts which would be foolproof in operation.

Accordingly it is an object of the present invention to provide a new and improved automatic phonograph.

It is another object of the present invention to provide a mechanical stop mechanism for an automatic phonograph which is simple and compact, of sturdy construction, and which will provide foolproof operationwithout in any way interfering with the function or operation of the automatic phonograph or record changer during 5 its normal record changing operation.

It is another object of the present invention to provide an automatic stop for a phonograph of the automatic record changer type in which the phonograph is automatically stopped following the playing of the last of a series of the records which are played consecutively.

It is a feature of the present invention to pro- 7 vide an automatic mechanical stop for a phonograph employing an automatic record changer in which the mechanism for feeding a record from the record stack to the turntable is rendered elfective to initiate the stopping of the record changer during the record changing cycle following the playing of the last of a series of records.

Further objects and advantages of the present invention will become apparent as the following description proceeds and the features of novelty which characterize this invention will be pointed out with particularity in the claims annexed to and forming a part of this specification.

For a better understanding of the present invention referenec may be had to the accompanying drawings in which:

Fig. l is a top plan view of an automatic record changer embodying the present invention;

Fig. 2 is a side view of the record changer of Fig. l but showing a stack of unplayed twelve inch records disposed in a record stack above the turntable;

Fig. 3 is a bottom view of the automatic record changer shown in Fig. 1 of the drawings with no records in the record stack; and

Fig. 4 is an enlarged semi-schematic perspective view of the stop mechanism of the record changer embodying the present invention with the parts in position for playing ten inch records, the stop mechanism in the position shown in Fig. 3 of the drawings, and the other parts of the mechanism in the positions assumed at an intermediate point during the record changing cycle.

In practicing the present invention there is provided on the stand for supporting the pe-- ripheral edges of the records of the record stack a pivotally mounted member engageable with the top surface of the topmost record in the record stack. When this member is moved to a lowered position, it normall being maintained out of this position by the presence of any records in the record stack, it causes the movement of a member into engagement with the record feeding mechanism so that subsequent actuation of the record feeding mechanism will operate a linkage mechanism for disconnecting the driving mechanism of the automatic phonograph and even cutting off the power supply to the motor for driving the phonograph and record changing mechanism, The automatic stop mechanism phonograph assembled thereon is then readily adaptable for mounting in a suitable cabinet, not shown, which cabinet may take any desirable form. Extending upwardly from the base member ill and rigidly fastened thereto is a spindle or center post i2, which extends well above the base W in a manner clearly indicated in Fig. 2 of the drawings. To insure the desired rigidity and to permit mounting the center post below the level of the base It, the latter is provided with a channel-shaped supporting member ll suitably fastened thereto as by welding or the like to which the spindle or center post 12 is fastened. Preferably this center post it? is of the form disclosed in my prior copending application Serial No. 576,202, filed February 5, 1945, now Patent No. 2,517,050, dated August 1, 1950, and assigned to the same assignee as the present application.

Center post 62 is illustrated as being provided with. a shoulder is so as to support a stack of unplayed records thereon. In addition, center post i2 is so formed that a slight lateral displacement of the lowermost record of the record stack supported on the shoulder 53 will cause release of this record so that it may slide down the center post i2 and onto a turntable l4 rotatable upon suitable bearing means coaxially arranged with post i2. Such a record indicated at L5 in Figs.

1 and 2 of the drawings is shown as having been moved into the playing position on the turntable i i. A plurality of records, such as i5, I5, etc, are illustrated as being disposed in the record stack supported on the shoulder 13 of the center post E2 in a manner to be described more fully hereinafter. The upper end of the spindle or center post !2 is preferably provided with a movable member I? for preventing any but the lowermost record of the record stack from being displaced laterally so as to be moved into playing position on the turntable. The pivotally mounted member 4! is so arranged as to permit removal or" the records from the turntable upon playing of all of these records without removing the center post i2 merely by raising the record stack from the turntable. This arrangement forms no part of the present invention but is disclosed and claimed in my prior copending application Serial No. M5202 referred to above.

For the purpose of further supporting the record stack, comprising the records 15, !5, etc., on the center post i2, there extends upwardly from the base it and in a manner so as to be clear of the turntable iii a vertical hollow post or stand which also houses the periphery engaging record ejecting mechanism. Essentially this record ejecting mechanism per se forms no part of the present invention, but is disclosed and claimed in my prior copending application Serial No. 697,878 referred to above. This record ejecting or record feeding mechanism comprises a member or rock arm 2| pivotally mounted about a transverse pivot or axes 22 within the stand 20. The upper end of the lever or rock arm 2| is provided with a portion Zia extending above the level of the post for engaging the edge of the twelve inch records, such as i5 for example, which is the bottom record in a stack of twelve inch records supported on the center post i2, for moving such record laterally a small distance to release it from the shoulder l3.

In order that the automatic phonograph may play a series of ten inch records there is associated with the upper end of the lever 2i a suitable mechanism actuable by an operator to cause the ejection mechanism to operate on ten inch records. This mechanism comprises a turnover plate 23 pivotally mounted as indicated at 252 to suitable members 25 and 26 fastened to the stand or vertical post 26. The particular construction of the turnover plate 23 forms no part of the present invention and is fully disclosed in prior copending application Serial No. 616,879, Endo, filed December 17, 19%, now abandoned, and assigned to the same assignee as the present application.

It will be understood that the automatic phonograph disclosed in the drawings will play either a stack of ten inch records or a stack of twelve inch records and the operator must selectively manipulate the turnover plate 23 in dependence upon whether ten inch or twelve inch records comprise the record stack on the shoulder is of the center post i2. When this is done the ejector mechanism comprising the rock arm 2i will automatically move either a series of ten inch records one at a time or a series of twelve inch records one at a time from the shoulder it to the turntable if; in proper sequence during the operation of the automatic phonograph.

In order to engage the peripheral edge of ten inch records the turnover plate .23 has slidably mounted thereon a reciprocally movable plate 2? arranged for guided reciprocal movement relative to plate 23 by means of a pin and slot connection specifically designated as 28 and 29 in Fig. 4. of the drawings. The end of the reciprocally movable plate or tongue remote from the edge of the record is provided with a forked portion 21a. for engaging a pin 39 in the upper end of the lever or rock arm 2!. It will be understood that the feeding or ejecting mechanism operates in exactly the same manner when a ten inch record is moved to the turntable as when a twelve inch record is moved to the turntable. In the case of a twelve inch record the portion 25a of the lever 21 directly engages the peripheral edge of the record and moves the same during a record feeding operation. In the case of a ten inch record the tongue or plate 2'5 directly engages the peripheral edge of a ten inch record but this plate is manipulated througha movement of the rock arm or lever 2!. When the turnover plate 23 is rotated to a position displaced by an angle of substantially more than ninety degrees in a counter-clockwise direction from that shown in Fig. 4 of the drawings to the position occupied by it in Fig. 2 of the drawings, the tongue 2? is disengaged from the pin of the rock arm or lever 2i and consequently no movement or the tongue 21 occurs in response to movement of the rock arm 2!.

Pivotally mounted to the upper portion of the post or stand 25 is a member 3i which is biased by suitable spring means, not shown, so that resilient extensions or pads 32 thereof engage the upper surface of the topmost record of the record stack supported on the shoulder l3 of the center post 12, thereby aiding in properly positioning the record stack. This manually actuated memher 3| is movable so that the operator may rotate it in a counter-clockwise direction, as Viewed in Fig. 2 of the drawings, to provide free access to the turnover plate 23 when setting up the phonograph for playing a stack of ten inch or twelve inch records and also to remove a stack of records from the turntable. It is apparent that this pivotally mounted element 3| is caused to move by gravity preferably supplemented by spring means, not shown, to lower and lower positions as successive records are moved from the record stack to the turntable, and finally when no records remain in the record stack the pivotally mounted member or element 3| is adapted to move to a predetermined lowermost position for performing a function which will be described in greater detail hereinafter. This lowermost position of the pivotally mounted member or element 3| will be hereinafter referred to as its functioning position.

Also extending above the base is a suitable tone arm 33 carrying the pickup unit including the needle or stylus 34 for engaging with the spiral sound groove indicated at 35 in the record 5. When the needle 34 has reached the end of the sound groove it may engage with a suitable lead in groove 36 provided in the record |5 causing the tone arm 33 to move towards the spindle |2 for a considerable distance within a very few revolutions of the turntable M. The tone arm 33 is the drawings and comprising a secondary tone arm 38. The end of the secondary tone arm 38 includes a pin or cam follower 39. The mechanism 3! forms no part of the present invention but is disclosed and claimed in my prior copending application Serial No. 699,961, filed September 28, 1946, now abandoned, and assigned to the same assignee as the present application.

Extending through the tubular tone arm shaft, not shown in the drawings, to which the tone arm 33 is rigidly connected and to which the mechanism including the secondary tone arm 38 is connected is a tone arm raise pin 4|] which operates in the conventional manner to raise the tone arm 33 at a predetermined instant during the record changing cycle and subsequently to lower the tone arm onto the particular record in playing position on the turntable l4. This raise pin 40 is actuated by means of a suitable cam 4| which is illustrated as being substantially identical in every respect with the rotatable cam disclosed and claimed in the copending Endo application referred to above. This cam 4| is mounted on a vertical axis as indicated in the drawings and the edge or rim portion 42 thereof forms a cam for actuating the raise pin 40 at the proper time durin a record changing cycle in a manner which will be appar ent to those skilled in the art. The rotatable cam 4| also includes a cam track for the cam follower 39 a large portion of which is defined between a raised portion 43 on the upper surface of the cam 4| and the rim portion 42. A portion of the cam track for the cam follower 39 is also defined between a slidable memberv 45 and either the rim 42 or the raised portion 43. The cam follower or pin 39 of the secondary tone arm 38 follows this cam track and consequently-controlsthe position of the tone arm 33 so as to move it clear of the turntable or backinto playing engagement with the record in playing position on the turntable |4.

.Theslidable member or segment 45 controls the initial positioning of the tone arm relative to the .record in playing position on the turntable in there is provided a manual control button 41 by means of which the phonograph may be controlled. This button may be used to turn off the phonograph, to selectively preset the mechanism for manual or automatic operation of thephonograph or to cause rejection of any record that is moved into playing position on the turntable. The function of the manual control. button 41 will be briefly described in connection with the mechanism which it actuates for purposes of a complete disclosure although it forms no part-of the present invention.

Referring now to the underside of the base In shown in Fig. 3 of the drawings, it may be observed that most of the mechanism is supported there out of the view of the operator. The cam 4| referred to above which esentially comprises a multiple of one cycle cams is suitably supported below the base I0 by means of a triangular shaped bracket 48 which is supported in a position somewhat parallel with the base H] by suitable supporting means depending from the base ID. The cam 4| is rotatable about one of the supporting means and is adapted to be actuated during the record changing cycle by the rotation of a pinion 49 engaging with the teeth 4|a. formed on the periphery-of the cam.4|. The pinion 49 is adapted to be driven at a predetermined time during the operation of the automatic phonograph by an electric motor generally indicated at 50 and supported from the base In. The particular construction of the motor 50 forms no part of the present invention, but is preferably of the type disclosed and claimed in a copending application of Earle W. Ballentine, Serial No. 711,694, filed November 22, 1946, now Patent No. 2,492,207, isued December 27, 1949, and assigned to the same assignee as the present application. This motor 50 also drives the turntable I4 as by suitable friction wheels, not shown, one of which is adapted to engage the rim of the turntable l4. The mechanism for controlling the drive of the turntable and the cam 4| forms no part of the present invention but is disclosed and claimed in m copending' application, Serial No. 535,218, filed jointly with Earle W. Ballentine on May 12, 1944, now Patent No. 2,480,623, dated August 30, 1949, and assigned to the same assignee as the present invention. To control the power supplied from a suitable source of electrcal energ indicated at 5| inFig. 4 of the drawings to the motor 50 there is provided a suitable switch 52 supported from the underside of the base I0.

In order to transmitthe motion produced by the adjustment of the button or manual control member 47 described above, it is connected to a crank 53 having a pin 54 which engages a slot 55a in a' manually actuable lever 55' which lever is pivotally mounted tothe base In as indicated at 56. This lever 5'5 is provided with a plurality of notches 5! engageable with a pin 58 which acts as a positioning means. Pin 58 is'mounted one, lever 59 suitably biased as by means of a spring 60 into engagement with the notched portions 51 of the lever 55. Lever 55 is also provided with a projection 55b which actuates the switch 52 which switch is provided with a suitable movable arm 52a engageable with the portion 55b of the lever 55 thereby controlling the power supplied to the motor 50 from the source 5| when the button 41 is moved to or from the olf position. Lever 55 also includes an extension 55c controlling a bell-crank 6| which when button 41 is moved to the off position moves the friction drive for the turntable l4 and the cam 4| to an inoperative position. When the button 41 is moved to the automatic position, the drive between the motor 56 and the cam 4| is rendered effective dependent, however, upon suitable releasable or latching means forming no part of the present invention which means control the initiation of the record changing cycle. This releasable means includes a trip lever 62 pivotally mounted to the base l0 and when this trip lever 62 is actuated it in turn moves a lever 63 to release the latching mechanism whereby the drive between the motor 56 and the cam 4| is rendered effective. When the button 41 is moved to the reject position, the end 55d of the lever 55 engages the trip lever 62 so as to actuate or initiate the record changing cycle immediately regardless of the position of the tone arm 33 relative to the record being played. When it is desired to play only a single record which is placed on the turntable, generally referred to as manual operation of the automatic phonograph, the button 41 is turned away from the stop position to the automatic position. As will become apparent from the following description, the phonograph will play this one record and then stop with the tone arm 33 free of the record so a new record can be positioned manuall on the turntable.

In order that the ejector mechanism including the lever 2| may be actuated at the proper time to release a record onto the turntable in synchronized relationship with the movement of the tone arm 33, the cam 4| is provided with an upwardly extending pin 65 which engages the end of a lever 66 pivotally mounted to the underside. of the base l0 and having one end connected by suitable means with the lower end of the lever 2|. Preferably, this connection between the lower end of the rock arm or lever 2| and the lever 66 pivotally mounted to the base ID as indicated at 61 includes a suitable spring 68 through which the force for feeding a record from the record stack to the turntable is transmitted.

The arrow in Fig. 4 of the drawings indicates the direction of rotation of the cam 4| during a record changing cycle and it may be observed that in the illustrated position the pin 65 is just about ready to engage the end of the lever 66 to cause actuation of the rock arm 2|. With this arrangement, it is obvious that at a predetermined point during the record changing cycle I and consequently during the cycle of the cam 4|,

the pin 65 causes pivotal movement of the lever 66 with theconsequent pivotal movement of the lever 2| to perform a record releasing function whereby thebottommost record such as l5'of therecordstack on the center post l2 is moved into, playing position onv the. turntable '|4.; A suitable spring 69 normally biases the-lever 66 into theposition indicated in Figs. 3 and 4 of the drawings so as to move the rock arm 2| to the non-record feeding position shown in Fig.2 of the drawings.

As is fully disclosed in the above-mentioned Endo application, the slidable segment 45 referred to aboveis provided with a pin 16 which engages I.

at a predetermined instant during the cycle of operation of the cam 4| with a trough-shaped cam member ll attached to a slide bar 12. The position of the slide bar 12 is controlled by the position of the turnover plate 23 referred to above as by means of a suitable lever 13 pivotally mounted as indicated at 14 within the stand or vertical support 20 and a suitable reciprocally movable pin 15 adapted to be engaged by an extension 23a of the-turnover plate 23. When the turnover plate 23 is in the position shown in Fig. 4 of the drawings, the pin 15 is biased downwardly by virtue of the extension 23a causing the pivotally mounted lever 13 to pivot in a clockwise direction, with the consequent result of pulling the slide bar 12 in a direction away from the center of the cam 4|. This, of course, will result in movement of the sliding segment 45 against the outer rim 42 as shown in Fig. 4 of thedrawings so as to position the tone arm for playing ten inch records. When the turnover plate 23 is moved to the position shown in Fig. 2 of the drawings, a suitable spring I? biases the slide bar l2 inwardly towardthe center of the cam 4| so as to move the segment 45 when pin 16 engages the trough H against the raised portion 43 of the cam with the consequent positioning of the tone arm 33 for playing twelve inch records. It is apparent that with this arrangement, the shape of a small portion of the cam track for the cam follower 39 is controlled properly to position the tone arm 33 in dependence upon whether a ten inch or twelve inch record is moved into playing position on the turntable. As is shown in Fig. 3 of the drawings, a flat spring member 18 engaging the bottom surface of the cam 4| insures that the movable segment 45 remains as set unless changed by the operation of the trough-shaped cam ll. The control of the cam track for the cam follower 39 by means of the trough-shaped cam H which is operated in response to the movement of the turn over plate 23 is fully disclosed and claimed in the copending Endo application referred to above.

In accordance with the present invention, it is desired to automatically stop the phonograph when the last record of a series of records disposed in the record stack above the turntable M has been moved into playing position on the turntable l4 and reproduced. In accordance with the present invention, such automatic stopping means is provided by employing a minimum number of parts and utilizing certain elements already provided to perform the additional function of stopping the phonograph. As was pointed out above, the member 3| pivotally mounted to the stand 26 engaging the top surface of the topmost record of the record stack moves to lower and lower positions as successive records are moved from the record stack to the turntable. It is apparent that the member 3| is capable of giving an indication of when no more records remain in the record stack. It should be understood, however, that although the present invention is illustrated as .utilizing the movement of the pivotally mounted member 3| for intiating' the stopping mechanism when no records remain in-the record stack, any other suitable means responsive to the movement of the last'record from the record stack onto the turntable may equally well be employed. Since the member 3| or a similar member is often incorporated in a record changer for steadying and aidingin the support of the records in the record stack, this member has been chosen to initiate the stopping mechanism since no additional parts are required. As is illustrated in my prior copendins application, Serial No. 607,878 referred to above, the member 3| is normally mounted on a suitable crank mechanism 8|] pivotally supported by stand 20. If desired, the biasing means for the pivotally mounted member 3| may be connected to the crank 8|! in a manner so as to provide an over-center arrangement whereby, when the pivotally mounted member 3| is in the position shown in Fig. 2 of the drawings, the spring not shown biases it downwardly and, when it is in a turned-over position to permit the removal of records or the replacement of a new series of records in the record stack, it biases the pivotally mounted member 3| in the opposite direction.

In order to utilize the movement of the pivotally mounted member 3| when moved to its functioning position, which is its lowermost position; following movement of the last record from the record stack onto the turntable, there is provided a reciprocally mounted pin 8| engageable by the crank 80. The lower end of the pin 8| engages a suitable L-shaped lever 83 hingedly mounted to a member 84 supported from the base it. The end of the L-shaped member 83, not hinged to member 84, is adapted to control the movement of one end of a rod or link 85. This rod or link 85 is provided with a hook-shaped portion 86 which may bemoved so as to engage one edge of the rock arm or lever 2|. A suitable spring 81 normally biases the rod 85, the L-shaped lever 83 and the pin 8| to a position out of engagement with the rock arm 2|.

In accordance with the present invention, there is provided a bell-crank 9E! suitably pivoted as indicated at 9| to the base Ill. The bell-crank 9|) is provided with a short arm 99a to which the other end of the rod 85 is connected as indicated at 92. The other arm of the bell-crank 90 extends over the cam 4| and is adapted to be moved into interfering position with the pin 65 as will be brought out hereinafter. Normally, the spring 81 moves the long arm of the bell-crank 90. to a position indicated in Fig. 1 of the drawings clear of the pin'65. The pivotally mounted bell-crank 90 also includes an arm 90; which is connected by means of a suitable link 93 with the lever 55. This connection between the link 93 and the lever 55 is illustrated as of the lost motion type comprising a pin and slot connection specifically designated at 94 and 95, respectively.

When the last record from the record stack has moved onto the turntable 4, the pivotally mounted member 3| engaging the top surface of such last record is permitted to move to its lowermost or functioning position with the result that the pin 8| and the L-shaped lever 83 move against the bias of the spring 87 to move the hook-shaped end 86 of the rod 85 into engagement with one surface of the rock arm 2|. When the last record has been reproduced by movement of the tone arm 33 in a normal manner across the record provided with the sound grooves 35, the record changing cycle is initiated and the cam 4| rotates to feed another record onto the turntable even though no record remains in the record stack. When the pin 65 engages the pivotally mounted lever 56 to perform a record feeding operation with respect to the rock arm 2|, reciprocal movement of rod 85 is also caused by virtue of the engagement of the hook-shaped end 86 thereof with the rock arm 2| with the consequent pivotal movement of the bell-crank 90 in a clockwise direction as viewed in Fig. 4 of the drawings. Such movement of the bell-crank causes the arm 90c thereof to 1i) move into a, position so as to be engaged by the pin 55 when it reaches a later position during the cycle of the cam 4|. Continued rotation of the cam 4| causes the pin 65 to move the bell crank 9|! sufliciently so that through link 93 lever 55 is pivoted not only to disengage the driving connection between the motor 59 and the cam 4| but also to disengage the driving connection between the motor 5!! and the turntable l4 and finally to open the switch 52 to deenergize the motor 55. It will be noted that the record feeding mechanism comprising the rock arm 2| is used to actuate the stopping mechanism and only a very slight additional force is required since the movement of the record feeding mechanism is not employed to actuate the lever 55 but is merely employed slightly to move the bell-crank into interfering position with pin 65 whereupon the latter mechanism capable of applying ample force performs the stoping operation. will be noted that the stop mechanism requires only the pin 8| the L-shaped member the rod 25, the bell-crank 90 and the link 93 in addition to the parts already present in the record changer, all of which parts may comprise simple stampings adding very little extra cost to the record changer to perform the automatic stopping operation.

In view of the detailed description included above, the operation of the automatic stop means for the record changing phonograph will be apparent to those skilled in the art and no addi tional description therefor is included herein. It will be understood that a very simple, sturdy mechanism adding substantially no additional cost to the record changer is provided which is foolproof in operation. This stop mechanism utilizes moving means already provided on the record changer.

Although a preferred embodiment of the presentinvention has been disclosed in complete detail so as to insure a complete understanding of the invention, it is contemplated that details of the disclosed structure are capable of modification and that other applications and features of the invention may occur to those skilled in the art. Hence, it is intended in the appended claims to cover all such modifications as fall within the true spirit and scope of the present invention.

- I claim:

1. In an automatic phonograph including a record changing mechanism, a rotatable turntable, means for supporting a stack of unplayed records above said turntable, a rotatable cam including a pin mounted thereon, driving means for said cam and said turntable, means for rendering said driving means ineffective to operate said cam at the end of said record changing cycle, record feeding means including a rock arm, a lever connected to said rock arm engageable by said pin during a record changing cycle in response to a predetermined rotation of said cam to cause the lowermost record of said stack to move into playing position on said turntable, a movable member disposed in an inoperative position as long as one or more records are disposed in said stack and movable to a functioning position following movement of the last remaining record of said stack onto said turntable, a rod disposed adjacent said rock arm having a hookshaped portion adapted to engage said rock arm in response to the movement of said member to said functioning position, pivotal means connected to said rod and movable to an interfering position relative to said pin in response to movement of said rock arm following movement of said member to said functioning position, means for rendering said driving means ineffective to drive said cam or said turntable, and means responsive to continued movement of said cam following movement of said pivotal means to said interfering position for actuating said last-mentioned means.

2. In an automatic phonograph including a record changing mechanism, a rotatable turntable, means for supporting a stack of unplayed records above said turntable, a rotatable cam operative during a record changing cycle to control a record changing operation, a motor for driving said cam, means for rendering said motor ineffective to drive said cam at the end of said record changing cycle, record feeding means 0perative during a record changing cycle in response to a predetermined rotation of said cam to cause the lowermost record of said stack to move into playing position on said turntable, a movable member disposed in an inoperative position as long as one or more records are disposed in said stack and movable to a functioning position following movement of the last remaining record of said stack onto said turntable, a rod having a hook-shaped end actuated in response to the movement of said member to said functioning position so that said hook-shaped end extends into the path of movement of a movable portion of said record feeding means, a bell-crank operatively connected to said rod and movable to a predetermined interfering position in response to movement of said rod upon operation of said record feeding means, means on said cam for engaging and moving said bell-crank following movement thereof to said predetermined interfering position, and means responsive to movement of said bell-crank for deenergizing said motor.

3. In a record changer, a changing mechanism, a rotatable turntable, means for supporting a stack of unplayed records above said turntable, a rotatable cam including a pin mounted thereon, a motor for driving said cam and said turntable, means for rendering said motor ineffective to operate said cam at the end of said record changing i cycle, record feeding means including a pivotally mounted rock arm, a lever connected to said rock arm engageable by said pin during a record changing cycle in response to a predetermined rotation of said cam to cause said rock arm to move the. lowermost record of said record stack into playing positionon said turntable, a sensing member disposed in an inoperative position aslong as at least one record is disposed in said stack and movable to a functioning position following movement of the last remaining record of said stack onto said turntable, a rod disposed adjacent said rock arm having a hook-shaped portion adapted to move into the path of movement of said rock arm in response to the movement of said sensing member to said functioning position, a bell-crank connected to said rod and movable to an interfering position relative to said pin in response to movement of said rock arm while said hook-shaped portion is disposed in the path of movement of said rock arm, switch means for controlling said motor, and means interconnecting said switch means and bell-crank whereby continued movement of said cam following movementof said bell-crank to said interfering position causes said pin to engage said bell-crank and move the same to open said switch.

4. Means as defined in claim 3 whereby said means interconnecting said switch means and bell-crank includes a lost motion connection.

5. Means as defined in claim 1, together with means for normally biasing said rod so that said hook-shaped portion is out of engagement with said rock arm.

SVEN A. STOLBERG.

REFERENCES CITED The following references are of record in the file of this. patent:

Johnson Oct. 11, 1949 

